Auto Focus or Manual Focus for Macro Photography
In macro and close-up photography situations, depth of field tends to become very shallow, so having control of your point of focus is very important.
In auto-focus mode you can position your point of focus by centering your subject in your frame, pressing and holding the shutter release button halfway, and then composing your image after your focus has been set on your subject. Be sure not to let go of the shutter release button once your focus has been set, or you will have to do the whole process over again.
If your digital point and shoot allows you to use manual focus controls, you can position your point of focus without readjusting your composition. Each camera is different, so refer to your owner’s manual to see whether yours offers manual focus and to learn how to use it.
This feature can come in handy when you really want to pinpoint the position of your focal point; however, manual focus on this type of camera can be slow and is mainly useful in situations where your subject is still.
Adjusting aperture enables you to change the depth of field in your photographs. Use a shallow depth of field to create selective focus — a technique that uses a shallow depth of field to isolate one sharp area among an otherwise blurry scene to draw viewers’ eyes to the selected area — or a great depth of field to maximize the amount of sharp detail in a scene.
If your point and shoot digital camera provides manual control of the aperture setting when shooting in macro mode select a smaller f/stop number (larger opening in the lens) to have a shallower depth of field and a larger f/stop number (smaller opening in the lens) to have a greater depth of field.
Aperture also affects exposure. In a low-light scenario, a smaller f/stop number lets in more light and enables you to reduce the time of your exposure.